Automatic feed for forging roll sets



VAug. 29, 1967 W. SCHILLER AUTOMATIC FEED FOR FORGING ROLL SETS 2 SheetsSheet 1 Filed July 28, 1964 R mm NL VCM WH C 6 R E N m w Aug. 29, 1967 W. SCHILLR 3,338,081

AUTOMATIC FEED F-OR FORGING ROLL SETS Filed July 28, 1964 l 2 Sheets-Sheet 2 /N VENTOR WERNER 50ML/51av @www ATTXS.

United States Patent AUTOMATIC FEED FOR FGRGING RLL SETS Werner Schiller, Leverkusen, Germany, assigner to Eumuco Aktiengesellschaft fur Maschinenbau, Leverkusen, Germany Filed July 28, 1964, Ser. No. 385,595

Claims priority, application Germany, July 29, 1963,

Claims. (Cl. 72-252) ABSTRACT OF THE DISCLOSURE An automatic feed mechanism is provided for feeding workpieces both parallel to and transversely of the axial direction of a pair of forging rolls having a plurality of forging tools spaced axially therealong. The transverse feed movement is effected by a crank rocker which is coupled to the forging roll drive and which reciprocates a pair of workpiece gripping tongs transversely toward and away from the forging tools in accordance with a generally sinusoidal function of displacement versus time and in synchronism with the rotation of the forging rolls. The parallel feed movement is effected by a workpiece carriage drive including a plurality of spaced abutments corresponding to the position of the axially spaced forging tools and a detent for engaging the abutments in sequence to sequentially position the workpiece opposite diierent forging tools to be moved toward and away from each tool in sequence by the transverse feed mechanism.

This invention relates to a novel automatic feed for forging or stretching roll sets for operating upon short workpieces and is particularly directed to roll sets of the type including rolling tools consisting of an upper and a lower forging roll `or sector disposed in juxtaposition, and an automatic feed for feeding a workpiece both in parallel and transverse directions relative to the direction of rotation of the forging rolls.

Endeavors have already been made, in forging roll sets of the type in which the rolling or forging tools are juxtaposed on an upper roll and a lower roll, to feed workpieces by means of workpiece tongs which are mounted in a feed system adapted to be moved longitudinally in the rolling direction and also transversely thereof. The movements performed by such tongs may be produced by hydraulically or pneumatcally operated piston cylinders. Thesequence of the movements of the tongs are controlled by such means as limit switches or other electropneumatically or electrohydraulically operated control devices. The movement of the workpiece tongs is synchronized relative to the movement of the rolling or forging toos by means of an electric control system which may include abutments or stops for contacting the limit switches. Since such electrohydraulic or electropneumatic control systems directly affect the working operation, undesirable faulty switching is an unavoidable but common occurrence. More particularly, because of the successive switching movements required during most forging operations a particularly rapid movement of the workpiece cannot be achieved, primarily because rapid undamped movement of these conventional workpiece feed devices toward abutments, stops and like control devices results in shocks and impacts. Consequentiy, a reliable synchronization between the movement of the rolling tools and of the workpiece cannot be effected by such prior art systems.

An object of this invention is, therefore, to provide an improved workpiece feed in forging roll sets of the type having juxtaposed rolling tools which is particularly characterized by means of coupling the workpiece feed system drive and the movement of the workpiece gripping and the sectors mounted thereon.

tongs to the drive for causing the movement of the forging rolls, and in this manner the movements of the tongs are precisely and accurately controlled by a direct mechanical connection of the means for driving the forging rolls with that for moving the tongs.

By the mechanism constructed in accordance with this latter object a positive connection between forge roll sectors or segments and the workpiece tongs insures that each workpiece is always situated in exactly the same position at the instant when the rolls bite, even at high operating speeds. In each phase of the operating process a positive relation exists between the position of the forging roll segments and the position of the workpiece tongs and the gripped workpiece.

It is also an object of this invention to provide means for causing a sinusoidal reversal of the direction and speed of movement of the feed tongs so that higher operating speeds are obtained without danger of shocks and impacts which otherwise occur in conventional tong feed means when brought into engagement with abutments or stops. In the disclosed embodiment of the invention the workpiece gripping tongs travel somewhat further between the rolls before the roll segments bite, so that the reversal of movement of the tongs takes place prior to the biting action of the rolls. In this manner the workpiece tongs reach a speed in the rolling direction which corresponds substantially to the rolling speed. This action coupled with the direct synchronization between the Workpieces, the tongs and the forging tools, reduces the electrical, hydraulic and pneumatic control means to a minimum, resulting in trouble-free and, above all, rapid forging operations.

Further, in accordance with this invention the tongs are advantageously mounted and guided in a feed arrangement consisting of a tongs carriage and a feed carriage. A rocker crank is also provided between the feed device and the forge roll driving device for `controlling the movement of the feed carriage in dependence upon the angle of rotation of the forge rolls. The transmission or drive ratio of the drive of the feed device in relation to the drive of the forging rolls depends upon the momentary length of the workpiece. A transmission ratio of 1:1 between the roll rotation and the reciprocating movement of the feed device exists if there are mounted on the roll periphery forge roll sectors which extend around 180 of the roll. In this manner the feed device reciprocates once during each single rotation of the roll. However, as an alternative it is possible in the case of very short workpieces to vmount two roll sectors each of about on the roll in a plane one behind the other with a gap of 90. In this manner the transmission ratio between the roll and the feed device is changed to 1:2, so that the feed device reciprocates twice during each single rotation of the roll It is a further object of this invention to provide a novel apparatus of the -type described in which the workpiece gripping tongs are arranged for displacement relative to the tongs carriage and movement of the feed carriage is against a constant axial compensating force as, for example, a hydraulically or mechanically acting spring. In addition, the tongs carriage may be maintained under a constantly acting traction force in a direction transverse to the direction of carriage feed. For limiting the lateral feed of the tongs carriage, adjustable abutments are provided, cooperating with a locking member as, for example, a pawl or the like, operated by a cam or the like of the tongs carriage.

A final object of this invention is to provide, in apparatus of the type described, tongs arranged for rotation about their longitudinal axis, and a cylinder which compensates for such rotational movement by means of a crank. In addition to the rotational movement of the tongs, the same also reciprocate through each 90 revolution so that rolling of workpieces in planes at 90 to one another is possible. The reciprocal feed of the tongs carriage is coupled to the rotational movement of the tongs by the release of the locking member or pawl through the rotation .of the tongs.

The invention shall be hereinafter described with reference to the embodiment illustrated in the drawings, in which:

FIG. 1 is a diagrammatic side elevational view of the forging roll feed apparatus according to the invention, and illustrates tongs carried by a reciprocal and rotatable t-ongs carriage gripping a workpiece positioned between upper and lower juxtaposed forging rolls; and

FIG. 2 is a top plan View of the apparatus illustrated in FIG. 1.

The apparatus of this invention includes a forging roll set comprising a lower roll 1 and an upper roll 2 on which are mounted forging or rolling tools 3 and 4 in a known manner. These rolling tools are arranged in juxtaposed relationship for performing various individual working operations, as shown in FIG. 2 of the drawings wherein a plurality of additional tools 4a, 4b, and 4c, each in the form of a 90 sector or segment, are shown carried by the roll 2. A workpiece 5 is gripped in workpiece gripping tongs 6. These tongs 6 may be closed and opened by means of a piston 7a driven, preferably hydraulically, by means of a pressure medium introduced into a hydraulic cylinder 7. Also provided in association with the tongs 6 is a guide tube 8 which is carried by a tongs carriage 9 for both rotatable and longitudinally displaceable movement. The rotational movement of the guide tube 8 and the tongs 6 is provided by a piston 10 (FIG. 2) adapted to be moved, for example hydraulically in a cylinder 10a by means of a pressure medium conventionally introduced therein. The piston 10 acts -upon a crank 11 so that the tongs 6 are rotated once clockwise and counterclockwise through 90 in each instance.

The tongs 6 are also moved in relation to the tongs carriage 9 in the longitudinal direction, i.e., toward and away from the rolls 1, 2 by a pair of conventional pistons 12 housed in hydraulic cylinders 12a into which is admitted and withdrawn hydraulic lluid, such as pressurized oil. The tongs 6 are pulled against a sleeve-like stop or abutment 14 by means of a cross member 13 secured t0 the pistons 12 by means of the pressure medium acting in the cylinders 12a. The cross member 13 is freely rotatably mounted in relation to the tongs guide tube 8, and the cylinders 12a are secured to the tongs carriage 9.

During the rotation of the tongs guide tube 8, by means to be hereinafter described, the tube 8 rotates a cam disc 15 secured thereto. A detent 18 is actuated by the cam dis-c 15 through a roller or cam follower 16 carried by a pivotally supported lever 17. The detent 18 acts against a plurality of stops or abutments 19 which are adjustably mounted lon a spindle 20, preferably by an external thread on the spindle (not shown) cooperative with threaded apertures (unnumbered) in each of the stops 19. The abutments 20 limit the lateral movement of the tongs carriage 9. Pressure medium introduced into and acting .in a cylinder 21 on a piston 21a pivots the lever 17 clockwise, as viewed in FIG. 1, to release the detent to an unlocked non-abutting relation relative to the stops 19 when ,the tongs carriage 9 is returned to its initial position (FIG. 1) in relation to the leading forging tool 4a after completion lof the rolling operation performed on the workpiece 5.

A driving gear 23 and a plurality of bevel gears 24 are in mesh, as is clearly sli-own in FIG. 2, at a predetermined gear ratio, by means of theprimary driving gear 22 of the forging roll set 1, 2. The total transmission or drive ratio between the roll set 1, 2 and a feed carriage 29 may vary, and it may be, for example, 1:1 or 1:2. The individual transmission ratios between the roll set gear 22 and the individual gears 23, 24 may differ from one another.

The feed carriage 29 is driven through a crank shaft 25 driven by one -of the gears 24. The crank shaft 25 engages with slide blocks 27 in two crank rockers or rocker arms 26a and 26b. The crank rockers 26a, 26b are connected to the feed carriage 29 through two links 28. As Was heretofore noted, the roll sectors 3, 4 embrace or less -of the rolls 1, 2. If `the roll sectors 3, 4 constantly rotated during the rolling an arcuate distance of 180 remains for a return feed of the workpiece 5 from left to right in FIG. 1. However, this angle of 180 is reduced to the extent of the angle of bite of the roll profile and by further amounts which are necessary for the reversal of the direction of movement of the workpiece tongs 6. That is, while the rolling of the workpiece 5 takes place over an angle of 180, the return feed of the workpiece into the next starting position must take place at an angle of less than 180. During one revolution of the rolling apparatus the crank rockers 26a, 26b rapidly pass through the angle a+,8=360. However, an angle a greater ythan 180 is available at the crank rockers 26a,

26b for the rolling operation, while the return takes place at a higher speed through the angle Therefore, the working or advancing stroke is produced bythe oscillating sliding rocker cranks at a speed suitable for the rolling operation, while the return stroke takes place at an accelerated speed.

The links 28 are adjustable in length by means of a device 30, such as a turnbuckle, so that the position of the workpiece tongs 6 is adjustable in relation to the center of the rolls 1 and 2. In this manner the head length, i.e. the unrolled length of the workpiece, is adjustable.

The feed carriage 29 is mounted in guides 31 which guide the reciprocating movement of the carriage 29 in the rolling direction during the movement thereof produced by the crank rockers 26a, 26b. The guides 31 are mounted in a frame 32. The feed carriage 29 also includes twoguides 33 for guiding the tongs carriage 9 in a transverse direction, as well as the spindle 20, which carries the adjustable abutments 19 for limiting this lateral movement. The tongs carriage 9 is also connected to the feed carriage 29 by means of a cylinder 34 housing a piston 34a which is under constant pressure urging the movement of the `piston to the right, as viewed in FIG. 2, to transversely feed the carriage 29 from one ofthe stops 19 to another when the locking device 18 is actuated, and performs the lateral feed into the initial position when the locking device 18 has been released by means of the cylinder 21. Y

The forging roll set feed described in the foregoing operates as follows:

The lower and upper rollers 1 and 2 are driven in a conventional manner known per se by means of a driving unit (not shown) comprising a clutch, a brake, a flywheel and an electric motor. When the apparatus is in the initial position, the upper and lower rolls 1, 2 are in the position illustrated in FIG. 1. Owing to the positive connection of the feed arrangement to these rolls, the tongs 6 are also in the illustrated position.

The tongs 6 are themselves opened by means of the pressure medium cylinder 7. The heated workpiece 5 is fed to the opened tongs from the left in FIG. 1. When the workpiece 5 has been introduced, the tongs 6 are closed by means of the pressure medium cylinder 7. TheV clutch (not shown) of the forging rolls 1, 2 is engaged, and the rolls 1 and 2 and the feed device are set in motion.

After a short idle movement within which the workpiece tongs 6 and the workpiece 5 have reached substantially the rolling speed, the roll sectors 3 and 4 bite and perform the rolling of the workpiece 5. The feed carriagek 29, and thus also the tongs carriage 9, travel in the rolling direction under the action of the crank linkages 26a and 26b. Any necessary correction of the speed of feed in relation to the rolling speed is effected by means of a compensation of the workpiece tongs 6 in the longitudinal direction in relation to the hydraulically actuated pistons 12 in the cylinder 12a. The speed of feed of the tongs carriage 9 is preferably slightly slower than the rolling speed, and this results in a small displacement of the tongs 8 in relation to the tongs carriage 9. This correction is generally necessary because the rolling speed depends upon the depth of the profile of the rolling sectors 3, 4 and because, by reason of the characteristic of the crank rockers 26a, 26b, only an approximately uniform speed of workpiece feed can be obtained.

When the workpiece leaves the rst rolling sector 4, the cylinders 12 bring the tongs 6 and the carriage back into engagement with the limiting member 14.

In the rear (right-hand) position of the crank rockers 26a, 26b the turning cylinder 10 is actuated by means of a hydraulic impulse and turns the tongs through 90 about their longitudinal axis. During this turning movement the detent 18 is released by means of the cam disc 15 in the manner heretofore described. This detent 18 releases the tongs carriage 9 for movement in the transverse direction and the cylinder 34 loaded towards the right can now move the tongs carriage transversely. The locking device 18 is released only for a short time during the turning of the tongs 8 so that when the next adjustable abutment 19 is reached the locking device 18 comes into contact with this abutment. Meanwhile, the direction of movement of the crank rockers 26a, 26b has been changed, and the reverse feed toward the left-hand position at increased speed through the range of the angle is effected.

After further reversal of the direction of movement, the workpiece 5 passes from left to right in the second roll prole 4b and, having been turned through 90, enters the initial position for the second rolling pass. Both the rolls 1 and 2 and the elements of the roll set feed move uninterruptedly during the rolling of the individual passes.

When the individual rolling operations have thus been performed, the roll set stops in the position illustrated in FIG. l and the tongs 6 are opened by means of the hydraulically actuated piston 7 and the cylinder 7a. The fully rolled workpiece 5 is then ejected. The tongs carriage 9 is then returned towards the left into the initial position at the roll sector 4a by means of the cylinder 34 when the locking device 18 is released by the cylinder 21. The rolling of another workpiece can then begin.

For changing the tools the entire feed apparatus may be run back from the rolls 1, 2. For this purpose the bevel gears 24 are connected through a loose shaft 35, by means of which the feed elements can be moved an appropriate amount away from the rolls 1, 2 without the breaking of the positive connection between the rolls 1, 2 and the feed apparatus. Consequently, no resynchronization between the rolls 1, 2 andthe feed apparatus is necessary.

While a preferred embodiment of the invention has been disclosed herein, various changes, modifications and arrangement of parts may be made without departing from the inventive scope of this disclosure as defined in the appended claims.

What is claimed is:

1. In a forge roll set including an upper forge roll and a lower forge roll disposed in juxtaposed relationship with forging tools mounted thereon, and means for driving said forge rolls in a perdetermined direction, a workpiece feed mechanism comprising a workpiece feed carriage, workpiece gripping tong means mounted on said workpiece feed carriage for movement transversely of said forging rolls toward and away from said forging tools thereon, and crank means connected between said gripping tong means and said drive means for said forge rolls for driving said workpiece gripping tongs transversely toward and away from said forging tools in accordance with a generally sinusoidal function of displacement versus time and in synchronism with the rotation of said forging rolls.

2. The forge roll set feed apparatus as defined in claim 1 wherein said workpiece gripping tong means comprises a pair of workpiece gripping tongs mounted on a tongs carriage which is mounted on said feed carriage, and wherein said crank means includes a crank rocker connected between said workpiece gripping tongs and said driving means for said forge rolls.

3. The forge roll set feed apparatus as defined in claim 2 wherein means is provided for adjusting the transmission ratio between the roll driving means and the feed carriage in dependence upon workpiece length.

4. The forge roll set as defined in claim 2 wherein said tongs are displaceable relative to said tongs carriage and said rolls, and means are provided for constantly biasing said feed carriage in a direction generallynormal to the direction of displacement of said tongs.

5. The forge roll set feed apparatus as dened in claim 2 wherein abutment means are provided for selectively limiting the movement of one of said carriages during a rolling operation performed upon the workpiece.

6. The forge roll set feed apparatus as defined in claim 2 wherein abutment means are provided for limiting the movement of one of said carriages during a rolling operation performed upon the workpiece, a locking member cooperative for releasable abutting contact with said abutment means, and means operative by said tongs carriage for actuating said locking member to lrelease the locking member from abutting contact with said abutment means.

7. The forge roll set feed apparatus as defined in claim 2 wherein said tongs are supported in a tube carried by said tongs carrier, and means for reciprocating and rotating said tube.

8. The forge -roll set feed apparatus as defined in claim 2 wherein said tongs are supported in a tube carried by said tongs carrier, means for reciprocating and rotating said tube, and means between said tube and said crank rocker means for controlling the rotation of said tube.

9. The forge roll set feed apparatus as defined in claim 6 wherein said crank rocker means are connected to one of said carriages by an adjustable linkage assembly.

10. The forge roll set feed apparatus as dened in claim 6 wherein mechanical connecting means are provided between the roll driving means and the feed carriage for disassembling the apparatus to remove the feed carriage away from said rolls.

References Cited UNITED STATES PATENTS Re. 13,377 3/ 1912 Blaxter 72-242 681,557 8/1901 Lay Bourne et al 72-421 822,879 6/1906 Briede 72-421 2,081,959 6/ 1937 Scoutten 72--252 RICHARD J. HERBST, Primary Examiner.

H. D. HOINKES, Assistant Examiner, 

1. IN A FORGE ROLL SET INCLUDING AN UPPER FORGE ROLL AND A LOWER FORGE ROLL DISPOSED IN JUXTAPOSED RELATIONSHIP WITH FORGING TOOLS MOUNTED THEREON, AND MEANS FOR DRIVING SAID FORGE ROLLS IN A PREDETERMINED DIRECTION, A WORKPIECE FEED MECHANISM COMPRISING A WORKPIECE FEED CARRIAGE, WORKPIECE GRIPPING TONG MEANS MOUNTED ON SAID WORKPIECE FEED CARRIAGE FOR MOVEMENT TRANSVERSELY OF SAID FORGING ROLLS TOWARD AND AWAY FROM SAID FORGING TOOLS THEREON, AND CRANK MEANS CONNECTED BETWEEN SAID GRIPPING TONG MEANS AND SAID DRIVE MEANS FOR SAID FORGE ROLLS FOR DRIVING SAID WORKPIECE GRIPPING TONGS TRANSVERSELY TOWARD AND AWAY FROM SAID FORGING TOOLS IN ACCORDANCE WITH A GENERALLY SINUSOIDAL FUNCTION OF DISPLACEMENT VERSUS TIME AND IN SYNCHRONISM WITH THE ROTATION OF SAID FORGING ROLLS. 